76 research outputs found
Unprecedented insights into extents of biological responses to physical forcing in an Arctic sub-mesoscale filament by combining high-resolution measurement approaches
In Fram Strait, we combined underway-sampling using the remote-controlled Automated Filtration System for Marine Microbes (AUTOFIM) with CTD-sampling for eDNA analyses, and with high-resolution optical measurements in an unprecedented approach to determine variability in plankton composition in response to physical forcing in a sub-mesoscale filament. We determined plankton composition and biomass near the surface with a horizontal resolution of ~ 2 km, and addressed vertical variability at five selected sites. Inside and near the filament, plankton composition was tightly linked to the hydrological dynamics related to the presence of sea ice. The comprehensive data set indicates that sea-ice melt related stratification near the surface inside the sub-mesoscale filament resulted in increased sequence abundances of sea ice-associated diatoms and zooplankton near the surface. In analogy to the physical data set, the underway eDNA data, complemented with highly sampled phytoplankton pigment data suggest a corridor of 7 km along the filament with enhanced photosynthetic biomass and sequence abundances of sea-ice associated plankton. Thus, based on our data we extrapolated an area of 350 km2 in Fram Strait with enhanced plankton abundances, possibly leading to enhanced POC export in an area that is around a magnitude larger than the visible streak of sea-ice
Molecular Characterization of the Plastidic Glucose-6-Phosphate Dehydrogenase from Potato in Comparison to its Cytosolic Counterpart
Stellar Rotation in Young Clusters. II. Evolution of Stellar Rotation and Surface Helium Abundance
We derive the effective temperatures and gravities of 461 OB stars in 19
young clusters by fitting the H-gamma profile in their spectra. We use
synthetic model profiles for rotating stars to develop a method to estimate the
polar gravity for these stars, which we argue is a useful indicator of their
evolutionary status. We combine these results with projected rotational
velocity measurements obtained in a previous paper on these same open clusters.
We find that the more massive B-stars experience a spin down as predicted by
the theories for the evolution of rotating stars. Furthermore, we find that the
members of binary stars also experience a marked spin down with advanced
evolutionary state due to tidal interactions. We also derive non-LTE-corrected
helium abundances for most of the sample by fitting the He I 4026, 4387, 4471
lines. A large number of helium peculiar stars are found among cooler stars
with Teff < 23000 K. The analysis of the high mass stars (8.5 solar masses < M
< 16 solar masses) shows that the helium enrichment process progresses through
the main sequence (MS) phase and is greater among the faster rotators. This
discovery supports the theoretical claim that rotationally induced internal
mixing is the main cause of surface chemical anomalies that appear during the
MS phase. The lower mass stars appear to have slower rotation rates among the
low gravity objects, and they have a large proportion of helium peculiar stars.
We suggest that both properties are due to their youth. The low gravity stars
are probably pre-main sequence objects that will spin up as they contract.
These young objects very likely host a remnant magnetic field from their natal
cloud, and these strong fields sculpt out surface regions with unusual chemical
abundances.Comment: 50 pages 18 figures, accepted by Ap
Abscisic acid effects on activity and expression of barley (Hordeum vulgare) plastidial glucose-6-phosphate dehydrogenase
Total glucose-6-phosphate dehydrogenase (G6PDH) activity, protein abundance, and transcript levels of G6PDH isoforms were measured in response to exogenous abscisic acid (ABA) supply to barley (Hordeum vulgare cv Nure) hydroponic culture. Total G6PDH activity increased by 50% in roots treated for 12 h with exogenous 0.1 mM ABA. In roots, a considerable increase (35%) in plastidial P2-G6PDH transcript levels was observed during the first 3 h of ABA treatment. Similar protein variations were observed in immunoblotting analyses. In leaves, a 2-fold increase in total G6PDH activity was observed after ABA treatment, probably related to an increase in the mRNA level (increased by 50%) and amount of protein (increased by 85%) of P2-G6PDH. Together these results suggest that the plastidial P2-isoform plays an important role in ABA-treated barley plants
Biomarker-based H-Print quantifies the composition of mixed sympagic and pelagic algae consumed by Artemia sp.
publisher: Elsevier articletitle: Biomarker-based H-Print quantifies the composition of mixed sympagic and pelagic algae consumed by Artemia sp. journaltitle: Journal of Experimental Marine Biology and Ecology articlelink: http://dx.doi.org/10.1016/j.jembe.2016.12.007 content_type: article copyright: © 2016 Elsevier B.V. All rights reserved
Miletus 2003–2005. Preliminary Report on the Excavations, Monument Restoration, Ruin Preservation as well as Natural Scientific Investigations – an Introduction and Overview
Der Beitrag gibt einen Überblick über die Aktivitäten der Miletgrabung in den Jahren 2003–2005 und fungiert daher als Einleitung zu den in diesem sowie dem nächsten Band des Archäologischen Anzeigers folgenden Artikeln. Wie in den vergangenen Jahren umfassten die Arbeitsbereiche in Milet sowohl Grabungen als auch Denkmälerrestaurierung und Ruinenpflege sowie naturwissenschaftliche Untersuchungen. Den Schwerpunkt bildeten die Grabungen im archaischen Heiligtum der Aphrodite auf dem heutigen Zeytintepe: Über sie wird ein eigener Vorbericht in diesem Band vorgelegt; außerdem sind einige kleinere Materialpublikationen aus den Grabungen hervorgegangen, die im nächsten Halbband der Zeitschrift veröffentlicht werden. Ausführlicher wird in der Einleitung auf die Ergebnisse der geophysikalischen Prospektion im Rahmen der interdisziplinären Programme der Miletgrabung eingegangen und versucht, sie in das Gesamtbild der Forschungen über die Stadt einzuordnen. Darüber hinaus werden die Arbeiten zur touristischen Erschließung des Ruinengeländes, über die kein eigener Bericht vorliegt, kurz zusammengefasst. Den Abschluss der Einleitung bildet ein Bericht von B. F. Weber über die Restaurierungsarbeiten im Theater von Milet.The article offers an overview of the activities of the Miletus excavation in the years 2003–2005 and thus functions as an introduction to the articles that follow in this and the next volume of the Archaeologischer Anzeiger. As in the last years, the work at Miletus consisted of excavations, the restoration of monuments and the preservation of ruins as well as certain natural scientific investigations. The main project was the excavation of the Archaic sanctuary of Aphrodite on the hill known today as Zeytintepe: a preliminary report specifically devoted to this subject follows in this volume, while a certain amount of material recovered during the excavations will be published in the next half-volume of the journal. The results of the geophysical prospection undertaken as part of interdisciplinary programmes of the Miletus excavation will be discussed in greater detail in the introduction, and the attempt will be made to integrate them into the overall picture of scientific research on the ancient city. In addition, there is a brief summary of the work done to present and develop the archaeological site for tourism, no report having yet been dedicated to the question. The introduction ends with an account of restoration work on the theatre of Miletus by B. F. Weber
Thessalische Weihreliefs an die apollinische Trias
Graeve (von) Volkmar. Thessalische Weihreliefs an die apollinische Trias. In: La Thessalie. Actes de la Table-Ronde, 21-24 juillet 1975, Lyon. Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1979. pp. 143-155. (Collection de la Maison de l'Orient méditerranéen. Série archéologique, 6
Projects at Miletus in 2006–2011
Den Schwerpunkt der Arbeiten bildeten die Ausgrabungen im milesischen Aphroditeheiligtum ›von Oikus‹, das im Rahmen des archaischen Programms entdeckt wurde und dessen Freilegung nun abgeschlossen ist. Das Zentrum seiner Topographie bildet ein Gipfelplateau als Standort der sukzessiv erfolgten Tempelbauten, von denen nur die Existenz eines kleinen Baus aus dem frühen 6. Jh. v. Chr. und eines großen spätarchaischen Tempels gesichert ist. Weitere topographische Fixpunkte sind die Westterrasse, deren Anfänge in einem aufgefüllten Steinbruch liegen und die mit den Funden aus dieser Auffüllung einen großen Teil der Votivgaben des Heiligtums geliefert hat, außerdem der Ostabhang mit einem Bothros, der in der Zeit um 630 v. Chr. geschlossen wurde und der mit dieser Datierung eine chronologische Neuorientierung im 7. Jh. v. Chr. notwendig macht. Gegraben wurde außerdem an einer Straße nördlich des Kalabaktepe, die nach der geophysikalischen Prospektion zum Straßenraster des spätarchaischen Stadtplans von Milet gehört hat. Die Grabung hat gezeigt, dass hier infolge des Niedergangs der Stadt nach der Perserzerstörung das neue urbanistische Konzept nicht vollständig umgesetzt wurde.Activities focused on the excavations in the Milesian sanctuary of Aphrodite ›of Oikus‹, discovered within the archaic program and now excavated completely. Its topographical center is a summit plateau, site of successive temple structures: of these, only a small 6th century building and a large late-archaic temple can actually be verified. One of the topographical points of reference is the western terrace which started out as a quarry and which has yielded, from its refill, a great part of the sanctuary’s votive donations. Furthermore, there is the eastern slope with a bothros that was sealed around 630 B.C., this dating necessitating a chronological revision within the 7th century B.C. There have also been digs at a road north of Kalabaktepe belonging – according to geophysical prospection – to the street grid of Miletus’ Late Archaic city plan. The excavation was able to show that no complete implementation of the new urbanistic concept took place in this region due to the decline of the city after its destruction by the Persians
Zum Zeugniswert der bemalten Grabstelen von Demetrias für die griechische Malerei
Graeve (von) Volkmar. Zum Zeugniswert der bemalten Grabstelen von Demetrias für die griechische Malerei. In: La Thessalie. Actes de la Table-Ronde, 21-24 juillet 1975, Lyon. Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1979. pp. 111-137. (Collection de la Maison de l'Orient méditerranéen. Série archéologique, 6
Zum Zeugniswert der bemalten Grabstelen von Demetrias für die griechische Malerei
Graeve (von) Volkmar. Zum Zeugniswert der bemalten Grabstelen von Demetrias für die griechische Malerei. In: La Thessalie. Actes de la Table-Ronde, 21-24 juillet 1975, Lyon. Lyon : Maison de l'Orient et de la Méditerranée Jean Pouilloux, 1979. pp. 111-137. (Collection de la Maison de l'Orient méditerranéen. Série archéologique, 6
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